An integrated 10 GHz quadrature LC-VCO in SiGe:C BiCMOS - technology for low-jitter applications

This paper presents an LC-VCO composed of a 20 GHz MOS-VCO and a bipolar 1:2 frequency divider. Combining the low phase noise inherent in MOS VCOs with the low power consumption of heterobipolar frequency dividers, a high-performance VCO with 50% duty cycle and a moderate power consumption of 25 mW is obtained. The contribution of the circuit to the absolute rms jitter of a 10 MHz-bandwidth PLL is lower than 130 fs.